GPT fdisk 0.8.3 release; minor bug fixes & feature changes.
diff --git a/diskio-unix.cc b/diskio-unix.cc
index 3735b9f..0bfceef 100644
--- a/diskio-unix.cc
+++ b/diskio-unix.cc
@@ -22,6 +22,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
+#include <unistd.h>
 
 #ifdef __linux__
 #include "linux/hdreg.h"